The invention relates to communication devices in general. More particularly, the invention relates to a method and apparatus for building an analytic model for a web server.
Over the past few years, the World Wide Web (xe2x80x9cWebxe2x80x9d) has seen tremendous growth, which is unlikely to slow down in the near future. The explosion of Internet Commerce and Telephony services brought the heretofore distinct Internet space into the realm of traditional telecommunications, and ensured that the Web will remain at the center of mainstream communications. At the heart of most Internet Commerce and Telephony service offerings is the Web server. Based on the Hypertext Transfer Protocol (HTTP) over the Transaction Control Protocol/Internet Protocol (TCP/IP), Web servers are expected to perform millions of requests per day at an acceptable Quality of Service (QoS) in terms of transaction throughput (connect and error rates) and latency (connect and response times) experienced by end users. To cope with the increasing volume of transaction requests, as well as the increasing demands of real-time communications, a thorough understanding of the performance capabilities and limitations of Web servers is crucial.
Web server performance is a complicated interplay between a variety of components, such as server hardware platform, Web server software, server operating system, network bandwidth, workload characteristics, disk caching, etc. Experience has shown that the performance of Web servers can be increased tremendously by the proper tuning of the server components. To properly configure these different components, however, it is crucial to understand how these components interact and how they impact user-perceived end-to-end performance.
To compare the performance of Web server platforms, numerous benchmarking tools have been brought to the market. The existing benchmarking tools, however, have a number of drawbacks. First, these tools consider the Web server as a xe2x80x9cblack boxxe2x80x9d, and as such fail to provide insight into how the individual components impact end-to-end performance. Second, benchmarking is extremely time-consuming, and experiments must be performed for many different workload scenarios. Third, benchmarking tools typically run on a workstation connected to a Web server, via a high-speed LAN, whereas in practice Internet-based end users are connected to the Web server via low-speed modems. Therefore, applying the outcomes of benchmarking experiments as an estimation of the actual Web server performance capabilities may lead to erroneous performance predictions.
In view of the foregoing, it can be appreciated that a substantial need exists for a method and apparatus which can evaluate and compare the performance of Web server platforms in an efficient and effective manner in order to solve the aforementioned problems.
The embodiments of the invention include a method and apparatus for modeling a web server. The server is modeled by identifying a plurality of sub-systems for the server. Each sub-system is represented as a queue, with each queue operably coupled to one another. An arrival rate and a service time is iteratively adjusted for each queue to account for performance by the other queues.
With these and other advantages and features of the invention that will become hereinafter apparent, the nature of the invention may be more clearly understood by reference to the following detailed description of the invention, the appended claims and to the several drawings attached herein.